1. Field
The present invention relates to a fluorescence detecting apparatus applied to a fluorescence observation system such as a confocal laser fluorescence microscope system, and a fluorescence detecting system thereof.
2. Description of the Related Art
Generally, a photomultiplier (hereinafter referred to as “PMT”) is used for a fluorescence detecting unit of a confocal laser fluorescence microscope. A barrier filter which transmits only the fluorescence of a particular wavelength band is disposed at the incident side of the PMT. Many fluorescence detecting units have a plurality of sets of PMTs and barrier filters mounted thereon in order to provide a plurality of wavelength bands (detecting channels) to be detected (see Patent Document 1: Japanese Unexamined Patent Application Publication No. 2006-220954, etc.). The number of sets of PMTs and barrier filters may be simply increased when providing additional detecting channels.
However, increasing the number of PMTs substantially increases the cost of the fluorescence detecting unit. Therefore, a method is conceivable in which a turret equipped with a plurality of barrier filters is used to switch the wavelength band of the fluorescence that can enter a single PMT (see Patent Document 2: Japanese Unexamined Patent Application Publication No. 2003-295064, etc.). By making the detecting channel of the PMT switchable in this manner, it becomes possible to increase the number of detecting channels while suppressing the number of PMTs.
However, acquiring a plurality of fluorescence images while switching the detecting channels of the PMT causes a time lag in the acquisition timing of individual fluorescence images.
Therefore, it is a proposition of the present invention to provide a fluorescence detecting apparatus which can easily speed up switching of detecting channels. In addition, it is also a proposition of the present invention to provide a fluorescence observation system which can acquire, at a low cost and as fast as possible, a plurality of fluorescence images having different wavelength bands.